JPEGThumbnailer.java

// [TODO: gota test this !!!]
package org.nees.buffalo.video;

import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

import com.rbnb.sapi.ChannelMap;
import com.rbnb.sapi.SAPIException;
import com.rbnb.sapi.Sink;
import com.rbnb.sapi.Source;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageDecoder;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

import COM.Creare.Utility.ArgHandler; //for argument parsing
import COM.Creare.Utility.RBNBProcess; //alternative to System.exit, so
                                       //don't bring down servlet engine

public class JPEGThumbnailer {

    private final static String DEFAULT_RBNB_SERVER = "localhost";
    private final static String DEFAULT_RBNB_PORT = "3333";
    private final static String DEFAULT_RBNB_OUTPUT_NAME = "TSource";
    private final static String DEFAULT_RBNB_OUTPUT_CHANNEL = "thumbnail.jpg";
    private final static String DEFAULT_RBNB_SINK_NAME = "JPEGThumbanilerSink";
    private final static double DEFAULT_SAMPLE_RATE = 1.0; // secondes

    private String rbnbServerName = DEFAULT_RBNB_SERVER;
    private String rbnbServerPort = DEFAULT_RBNB_PORT;
    private String rbnbHostName = rbnbServerName + ":" + rbnbServerPort;
    private String rbnbSourceName = DEFAULT_RBNB_OUTPUT_NAME;
    private String rbnbSourceChannel = DEFAULT_RBNB_OUTPUT_CHANNEL;
    
    private String rbnbSinkName = DEFAULT_RBNB_SINK_NAME;
    
    private String rbnbInputPath = null; // required

    private double outputSampleRate = DEFAULT_SAMPLE_RATE; // seconds

    private static void printUsage()
    {
        System.out.println("Usage for JPEGThumbnailer...");
        System.out.println("  -v RBNB Sink (input video) path (required) ");
        System.out.println("  [-r RBNB Server Name *"+ DEFAULT_RBNB_SERVER + "]");
        System.out.println("  [-p RBNB Server Port *" + DEFAULT_RBNB_PORT + "]");
        System.out.println("  [-s RBNB Source (output) Name *" + DEFAULT_RBNB_OUTPUT_NAME + "]");
        System.out.println("  [-c RBNB Source (output) Channel *" + DEFAULT_RBNB_OUTPUT_CHANNEL + "]");
        System.out.println("  [-f desired output frame rate (in seconds)*" + DEFAULT_SAMPLE_RATE + "]");
    }
    
    public JPEGThumbnailer(String[] args)
    {
        //parse args
        try {
            ArgHandler ah=new ArgHandler(args);
            if (ah.checkFlag('h')) {
                printUsage();
                RBNBProcess.exit(0);                
            }
            if (ah.checkFlag('r')) {
                String a=ah.getOption('r');
                if (a!=null) rbnbServerName=a;
            }
            if (ah.checkFlag('p')) {
                String a=ah.getOption('p');
                if (a!=null) rbnbServerPort=a;
            }
            if (ah.checkFlag('s')) {
                String a=ah.getOption('s');
                if (a!=null) rbnbSourceName=a;
            }
            if (ah.checkFlag('c')) {
                String a=ah.getOption('c');
                if (a!=null) rbnbSourceChannel=a;
            }
            if (ah.checkFlag('v')) {
                String a=ah.getOption('v');
                if (a!=null) rbnbInputPath=a;
            }
            if (ah.checkFlag('f')) {
                String a=ah.getOption('f');
                if (a!=null) outputSampleRate = Double.parseDouble(a);
            }
        } catch (Exception e) {
            System.err.println("JPEGThumbnailer argument exception "+e.getMessage());
            e.printStackTrace();
            RBNBProcess.exit(0);
        }

        if (rbnbInputPath == null)
        {
            System.err.println("The source/channel path for the video source is required. "
                + "Use JPEGThumbnailer -h for help");
            RBNBProcess.exit(0);
        }

        rbnbHostName = rbnbServerName + ":" + rbnbServerPort;       
    }
    
    private void execute() {
        // open connection to RBNB server as a sink
        Sink sink = new Sink();
        try {
            sink.OpenRBNBConnection(rbnbHostName, rbnbSinkName);
        } catch (SAPIException e) {
            System.err.println("Failed to connect to RBNB server for sink (video input).");
            e.printStackTrace();
            return;
        }
                
        // select input channel to monitor
        ChannelMap reqmap = new ChannelMap();
        int inputChannelIndex = -1;
        try {
            inputChannelIndex = reqmap.Add(rbnbInputPath);
        } catch (SAPIException e) {
            System.err.println("Failed to add input channel to channel map.");
            e.printStackTrace();
            return;
        }
        
        // monitor input channel for data
        try {
            //sink.Subscribe(reqmap);
            sink.Monitor(reqmap, 0);
        } catch (SAPIException e) {
            System.err.println("Failed to monitor input channel.");
            e.printStackTrace();
            return;             
        }       
        
        // connect to RBNB server as source
        Source source = new Source(10, "none", 0);
        try {
            source.OpenRBNBConnection(rbnbHostName, rbnbSourceName);
        } catch (SAPIException e) {
            System.err.println("Failed to connect to RBNB server for source.");
            e.printStackTrace();
            return;             
        }           

        // select channel to output data to
        ChannelMap cmap = new ChannelMap();
        int outputChannelIndex = -1;
        try {
            outputChannelIndex = cmap.Add(rbnbSourceChannel);
        } catch (SAPIException e) {
            System.err.println("Failed to add output channel to channel map.");
            e.printStackTrace();
            return;             
        }           
        cmap.PutMime(outputChannelIndex, "image/jpeg");         
                
        byte[] imageData;
        double startTime = 0;
        double oldStartTime = 0;
        double durationTime = 0;
        int imageIndex = 0;
        double averageInputSampleRate = 30;
        while (true) { //loop forever, receiving JPEG frames        

            // see if any data is available from source
            ChannelMap getmap = null;
            try {
                getmap = sink.Fetch(1000);
            } catch (SAPIException e) {
                System.err.println("Failed to fetch input data, retrying.");
                continue;
            }                   
                
            // no data received, try again
            if (getmap.GetIfFetchTimedOut()) {
                System.err.println("Data request timed out, retrying.");        
                continue;
            }
                        
            oldStartTime = startTime;           
            startTime = getmap.GetTimeStart(inputChannelIndex);
            durationTime = getmap.GetTimeDuration(inputChannelIndex);
            imageData = getmap.GetData(inputChannelIndex);

            // calculate instantaneous sample rate
            double sampleRate;          
            if (imageIndex > 0) {
                sampleRate = 1/(startTime-oldStartTime);
            } else {
                sampleRate = 30;
            }
            
            // time between sample is too close (or the same)
            if (Double.isInfinite(sampleRate)) {
                sampleRate = averageInputSampleRate;
            }
        
            // calculate average sample rate
            averageInputSampleRate = averageInputSampleRate*0.995 + sampleRate*0.005;
            
            /* calculate the number of frames to skip,
             * roundedFramesToSkip-1 is the actual number of frames skipped
            */
            long roundedFramesToSkip = Math.round(averageInputSampleRate/outputSampleRate);
            if (roundedFramesToSkip < 1) {
                roundedFramesToSkip = 1; 
            } else if (roundedFramesToSkip > averageInputSampleRate){
                roundedFramesToSkip = 1;
            }
        
            // only create thumbnail if we have skipped enough frames       
            if (imageIndex % roundedFramesToSkip == 0) {
                
                System.out.print("Receiving " + ((double)Math.round(averageInputSampleRate*10))/10 + " fps and converting to " + outputSampleRate + " fps    \r");

                JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(new ByteArrayInputStream(imageData));
    
                // decode JPEG image to raw image
                BufferedImage bi;
                try {
                    bi = decoder.decodeAsBufferedImage();
                } catch (IOException e){
                    System.err.println("Failed to decode input JPEG image, skipping.");
                    continue;
                }
    
                // scale both width and height by 0.5
                AffineTransformOp op = new AffineTransformOp(AffineTransform.getScaleInstance(0.5, 0.5), null);
                bi = op.filter(bi, null);
                
                // encode scaled image as JPEG image                
                ByteArrayOutputStream out = new ByteArrayOutputStream();
                JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
                JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(bi);
                param.setQuality(0.75f, false);         
                try {
                    encoder.encode(bi, param);
                } catch (IOException e) {
                    System.err.println("Failed to encode output JPEG image, skipping.");
                    continue;
                }               

                // get JPEG image data as byte array
                imageData = out.toByteArray();
    
                // put data in channel map, preserving original time stamp
                try {
                    cmap.PutTime(startTime, durationTime);
                    cmap.PutDataAsByteArray(outputChannelIndex, imageData);
                } catch (SAPIException e) {
                    System.err.println("Failed to put output data to channel map, skipping.");
                    continue;               
                }   
                
                // send data to RBNB server
                try {
                    source.Flush(cmap, true);
                } catch (SAPIException e) {
                    System.err.println("Failed to flush output data to server, skipping.");
                    continue;               
                }   
            
            }
            
            imageIndex++;
        }
    }

    public static void main(String[] args) {
        JPEGThumbnailer t = new JPEGThumbnailer(args);
        t.execute();
    }
}

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